Grabhooks



April 14, 1942.

- J. KAMPP GRAB HOOK To Hn/ls'T/y Mechanism.

Filed June` 6, 1941 A TTa//VE Y Patented Apr. 14, 1942 UNITED STATESPATENT OFFICE `2,279,570 GnABnoiis Jacob Kamppi, Astoria, Oi'eg.Application June a, 1941, serial No. 396,883 v Claims. (lol. 2'94112) Myinvention relates to load lifting and engaging apparatus and isparticularly designed for use in lifting round or cylindrically-shapedobjects. In this connection, it has particular utility in loading logs.At the present time it is a common practice to engage logs, eitherv inloops or bights of line, or to Vengage them in tongs having relativesharp `points which sink into the logs and are thus secured thereto.With tongs of this character,v the logs are frequently punctured to sucha depth that a substantial amount of lumber is thus damaged. This isrelatively unimportant when logs are used to make rough timbers, but isquite important when so-called` peeler logs are loaded. Peelerf logs areused in making veneer stock and the most valuable portion of the log isthe external surface thereof, because such surface is more free ofknots, pitch pockets and other defects and thus produces more clear plyor veneer stock.

Logs are normally stacked on a truck or on a flat car in a pile and thusthe loading mecha# nism must be designed so that the loading tongs orlines can be freely disengaged without disturbing the stackedrelationship. Thus, if loops or bights of line are used for liftingy thelogs, the line cannot freely be removed without tending to roll thelogs, with consequent disturbance to the stack and consequent danger tothe operator.

The object of my invention is to provide tong devices in load engagingapparatus of lthis character, which may engage the logs securely butwithout damaging them; said tongs' are also designed so that they willopen yonly sufficiently to take hold of a log or other object, toquickly and rmly engage a log and lift it into position. The connectionsare arranged so that the tongs can be easily and quickly disengaged,frequently without manual aid of an operator at the tongs.

A further and more specic object of my invention is to providetongs ofthis character, which may engage spherical or irregular objects, similarto so-called grappling hooks, and may set such objects down withoutcausing them to roll.

Further and other detailed objects and advantages of my invention arehereinafter referred to with reference to the accompanying drawing, inwhich:

Fig. l is a more or less diagrammatic view of a spar' tree and loadingboom, utilizing load engaging apparatus involving my invention;

Fig. A2 is a plan View of loading tongsl embody ing my invention,looking downwardly upon the upper or non-work engaging faces thereof; l

Fig. 3 is a side elevation of such tongs, with portions shown brokenaway to disclose details of construction;

Fig. 4 is av sectional view taken substantially on the line 4-4 in Fig.3, illustratingthe manner in which said tongs may be utilized forgripping an object of circular cross section; and l Fig, 5 is asectional view taken on the line 5-`5 in Fig. `3, showing a sectionaldetail of one of said tong members. Y

My invention concernsmost directly, the constructioncof tong devices andload engaging apparatus, which devices comprise a pair of tong members land Y2, pivotally joinedtogether at one end by a bolt 3. Said boltconnection purj p'osely is not varranged at the vextreme end of thistong member, thus the end la of tong memberV i extends beyond thepivotal bolt connection and engages a flange 2a on the other tongmember. This limits the outward movement ofthe tong members as isillustrated in Fig. 3. The tongs may be swung forwardly to the positionshown in Fig. 3 as the outermost limit, and I prefer that said tongsl beopenable to a lesser degree'. I preferably define the maximum dis-ltance to which `the tong members may bexspread apart to a position inwhich vthe extremities Ib and 2b are arranged substantially inparallelism.`

It is .to be noted that the tong members are curved or cupped upon arelatively wide sweep and said extremities carry prongs thereon whichextend normal to the sweep of the tongs at that point. Saidk prongs faceinwardly that is, toward each other, and arev of such lengths that theyare shorter thanthe degree of cupping of each of the tong members. Ipreferably proportion saidtong members I and 2 and the engagement of theends la and 2a, respectively, so that the tong members maybe arranged tostraddle an object with the extremities parallel rather than slightlydivergent as shown in Fig. 3. Thus,y

when the tongs are lifted by the mechanism hereinafter described, saidextremities lb and 2b may move quickly toward each other vto engage alog 5 or a boulder 6 by its sides with the prongs 4 arranged slightlybelow the diameter thereof. That is, said log or boulder is arranged inthe cup of the tongs and the prongs 4 onlyprovide means to prevent thelog or boulder from'slip` ping out of the prong member. The prongs', ofcourse, may not easilyv dig into a rock or other hard objectxandit is"essential that they ynot puncture a barrel or other container-l It isnot desirable either that said prongs project thru the bark of a log tomake holes in the outer or sapwood of the logs as has previously beencommented upon.

Each of the tong members is provided with a series of corrugations 'Iwhich form projecting longitudinally extending ribs 8 to prevent thetongs from slipping longitudinally of the log, and to accommodate anyirregularity in a boulder or other circular or spherical object. Theprongs are also corrugated, ribbed or otherwise serrated, as is shown inFig. 5, so that therev is a multiplicity of points 4a underlying theobject or en-l Another set of lines is provided for lowering andreleasing the tongs. These lines include a bridle section of chain 22.That is, said chain is bifurcated, one end 22a being secured to link I6and another end 22h being secured to bracket I2 as is illustrated inFig. 3. Said length of chain.

is to be disengaged or released from the tongs,

gaging to a limited extent, the periphery of the object held by thetongs. Then said tongs preferably diverge toward their extremities asshown in Fig. 2 and longitudinal anges 9 extend along their longitudinalmargins. Said anges extend away from the engaging surface of the tongsand provide stiffness for said tongs. The corrugations 'I extendfan-shaped toward the extremities, that is, they diverge toward theextremities as shown in Fig. 2, and thus said corrugations tend to forma plurality of Vs on'the gripping surface of the tongs to preventlongitudinal slipping of the object in said tongs withoutdamaging thesurface unduly, which supplement prongs 4 in their action.

The pivotal bolt connection 3 for the tong member passes thru theflanges of the tong members, as is shown in Figs. 2 and 3 and alsosecured between such anges adjacent to said pivotal connection is abracket I carrying Ia sheave II. Another bracket I2 is riveted, boltedor welded to the back of tong member I and carries a sheave I3journalled therein. Said bracket I2 is secured to the back of tongmember I at a point intermediate the ends of the latter,V as is shownmost clearly in Figs. 3 and 4 and preferably is arranged at a pointabove the top of any potential load to be engaged by said tongs as isshown in Fig. 4. Said bracket I2 overlles |an elongated slot I4 in tongI, so that the sheave I3 may extend into said slot a substantialdistance.

A exible element such as, for example, chain I5 is secured to a link I6,passing thru and engaging the tong member 2 at a point thereonsubstantially opposite sheave I3. Said ilexible element or chain I5extends across the space between the tong members land takes a bightaround sheave I3 and another bight under sheave II and is joined to oneend ofl a cable I'I, which, in turn, is connected to a hoistingVmechanism, indicated but not shown in Fig. 1. Preferably, when the logsare being loaded, there are two sets of tong members carried by orsuspended from a loading boom I8 supported and extending laterally froma spar tree I9. Thus, one set of tong members is secured to one end ofsaid cable I'I and the other set to the other end f thereof. Loadingline 20 passes thru a block 2| engaging an intermediate portion of thecable I'I; thus both sets of loading tongs are lifted simultaneously. Itis not to be assumed that the specific rigging arrangement is requiredto practice my invention, but the type shown is illustrated to discloseone embodiment of my invention and its means of. use. When the loadingline 20 is pulled by the loading mechanism, it

takes up the slack in chain I5 and pulls the extremities of the tongstoward each other to engage a log as shown in Fig. 1. Further. pull onsaid loading lines causes both ends of the log to be lifted upwardlytoward the under sideof the loading boom.'

the loading line is slacked oif and the lowering line 24 is made taut.This tends to pull the tong Y members apart by pulling on the cable endsin the direction shown in arrows in Fig. 3. It is to be understood thatthe tong members are quite heavy and have substantial mass and the upperor pivoted ends of the tong members are substantially heavier than theextremities thereof. Thus when the tongs are supported by chains 22, thecentral portion, including the pivotal connection, bracket I0, sheave IIand-the other mechanisms thereto, tend to move downwardly until the endI a abuts with the flange 2a to limit the outward movements thereof.Thus, by putting tension in the lowering line 23, a .log or other objectcan be readily disengaged from the tongs without much effort. Also, thelog or other object does not tend to roll, because the tongs arearranged only at the side of the log or other object and move directlyaway from said side, without tending to roll or tip thelog or otherobject, in effecting its disengagement. Thus the tongs embodying myinvention set the log or other object down without any great difficulty.

Inasmuch as my invention does not pertain directly to the details of theloading mechanism nor to the specific rigging therefor, I have notattempted to describeall of the details of the rigging nor the manner inwhich the logging boom is secured t0 the spar tree. As a matter of fact,my invention is not limited to operating with a logging boom or spartree, but is adaptable to any type of loading apparatus or riggingtherefor. It relates to the rigging only assaid rigging is necessary tolift the tongs, bring them together to engage lan object and todisengage them, when the object engaged is .to be released,

as I have previously described,

I claim:

1. In load engaging apparatus, a pair of `tongs pivotally joinedtogether adjacent one end, the opposed faces of said tong members beingslightly curved toward eachother and inturned serrated prongs formed atthe free extremities of each of said tong members, extendingsubstantially normal to thecurved face of each tong member, said prongsbeing of such length .as to b e less than the maximum Vrise of the'arcformed by the tong member upon which they are for-med.

2. In load engaging apparatusya pair of vtongs pivotally joined togetheradjacent one end, the opposed faces of said tong members being slightlycurved toward each other, and longitudinally extending ribs extendingfan-shaped alongthe face of each of said tong members.

3. In load engaging apparatus, a pair of tongs pivotally joined togetheradjacent one end, the opposed faces of saidv tong members being slightlycurved toward each other, operating connections for said tongscomprising a flexible element secured to o'netong member and engagingthe other in a bight of said element, functioning to draw said memberstowards each other and to lift said tongs, means for spreading said tongmembers apart, and a stop for said tongs limiting the relative outwardmovement thereof to a point where the free extremities of said tongs arein substantial parallelism with each other.

4. In load engaging apparatus, a pair of tongs pivotally joined togetheradjacent one end, the opposed faces of said tong members being slightlycurved toward each other, operating connections for said tongscomprising a iiexible element secured to one tong member and engagingthe other in a, bight of said element, functioning to draw said memberstowards each other and to lift said tongs, a guide element secured tosaid tongs adjacent their pivotal connection, about which guide elementsaid iiexible element passes, and a bridled connection joined to saidtong members adjacent the point of securing and engaging of saidflexible member, respectively, with the tong members for spreading saidtong members apart.

5. In load engaging apparatus, a pair of tongs pivotally joined togetheradjacent one end, the opposed faces of said tong members being slightlycurved toward each other, operating connections for said tongscomprising a exible element secured to one tong member and engaging theother in a bight of said element, functioning to draw said memberstowards each other and to lift said tongs, a guide element secured tosaid tongs adjacent their pivotal connection, about which guide elementsaid flexible element passes, a bridled connection joined to said tongmembers adjacent the point of securing and engaging of said exiblemember, respectively,

with the tong members for spreading said tong members apart, and acommon link securing said connections and said flexible element to atong member.

6. In load enga-ging apparatus, a pair of tongs pivotally joinedtogether adjacent one end, the opposed faces of said tong members beingslightly curved toward each other, inturned serrated prongs formed atthe free extremities of each of said tong members, extendingsubstantially normal to the curved face of each tong member, v

.opposed faces of said tong members being slightly curved toward eachother, inturned prongs formed at the free extremities of each of saidtong members, extending substantially normal to the curved face of eachtong member, said prongs being of such length as to be less than themaximum rise of the arc formed by the tong member upon which they areformed, operating connections for said tongs comprising a flexibleelement secured to one tong member and en. gaging the other in a bightof said element, functioning to draw said members towards each other andto lift said tongs, means for spreading said tong members apart, and astop for said tongs limiting the relative outward movement thereof to apoint where the pronged ends are in substantial parallelism with eachother.

' JACOB KAMPPI.-

